Department Seminar: Alex Guenther
Title: Landscape heterogeneity and reactive biogenic volatiles: From the Amazon to urban US
Abstract: Terrestrial ecosystems emit a broad range of volatile compounds into the atmosphere with lifetimes that range from a few minutes to many years. This includes highly reactive volatile organic compounds (VOCs) emitted by vegetation that play critical roles in signaling among organisms, ecosystem functioning and health, and atmospheric chemistry and climate. Atmospheric distributions of short-lived VOCs can be highly variable over heterogenous landscapes, especially terpenoid compounds that are emitted by some but not all plant species. The importance of understanding and characterizing biogenic VOC variability will be discussed including the role of chemical segregation, identification of primary versus secondary compounds, and the change in their atmospheric fates. The implications for local to regional atmospheric chemistry and air quality will also be presented. This will include results from field studies in heterogeneous locations extending from US cities to the remote Amazon, and places in between. The need for quantifying fine scale landscape heterogeneity will be demonstrated and new approaches for accomplishing this on local to global scales will be described.